Use an app like TagDiskHD (get the free version, there's no difference bar ads) TagDisk is for saving downloaded files to your iPad. You need to log onto BT in the inbuilt browser, then download the mp3. After download you can listen to it in the app too (note you can't add to Music app this way, you'd need iTunes). A little fiddley but I've listened to things this way for almost a year and it works a treat.